PIbd-31_COP6/BookDatabaseImplement/Implements/ReaderStorage.cs

using BookContract.BindingModels;
using BookContract.StorageContracts;
using BookContract.ViewModels;
using BookDatabaseImplement.Model;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BookDatabaseImplement.Implements
{
    public class ReaderStorage : IReaderStorage
    {
        private Reader CreateModel(ReaderBindingModel model, Reader reader)
        {
            reader.Name = model.Name;
            return reader;
        }

        private ReaderViewModel CreateModel(Reader reader)
        {
            return new ReaderViewModel
            {
                Id = reader.Id,
                Name = reader.Name
            };
        }

        public List<ReaderViewModel> GetFullList()
        {
            using var context = new BookLibraryDatabase();
            return context.Readers.ToList().Select(CreateModel).ToList();
        }

        public List<ReaderViewModel> GetFilterList(ReaderBindingModel model)
        {
            using var context = new BookLibraryDatabase();
            return context.Readers
                .Where(reader => reader.Name.Contains(model.Name))
                .ToList().Select(CreateModel).ToList();
        }

        public ReaderViewModel? GetElement(ReaderBindingModel model)
        {
            using var context = new BookLibraryDatabase();
            var reader = context.Readers.FirstOrDefault(rec => rec.Id == model.Id || rec.Name == model.Name);
            return reader != null ? CreateModel(reader) : null;
        }

        public void Insert(ReaderBindingModel model)
        {
            using var context = new BookLibraryDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                context.Readers.Add(CreateModel(model, new Reader()));
                context.SaveChanges();
                transaction.Commit();
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }

        public void Update(ReaderBindingModel model)
        {
            using var context = new BookLibraryDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var reader = context.Readers.FirstOrDefault(rec => rec.Id == model.Id);
                if (reader == null)
                {
                    throw new Exception("Читатель не найден");
                }
                CreateModel(model, reader);
                context.SaveChanges();
                transaction.Commit();
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }

        public void Delete(ReaderBindingModel model)
        {
            using var context = new BookLibraryDatabase();
            var reader = context.Readers.FirstOrDefault(rec => rec.Id == model.Id);
            if (reader != null)
            {
                context.Readers.Remove(reader);
                context.SaveChanges();
            }
            else
            {
                throw new Exception("Читатель не найден");
            }
        }
    }
}